1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2015 Josh Poimboeuf <jpoimboe@redhat.com>
4 */
5
6/*
7 * objtool:
8 *
9 * The 'check' subcmd analyzes every .o file and ensures the validity of its
10 * stack trace metadata.  It enforces a set of rules on asm code and C inline
11 * assembly code so that stack traces can be reliable.
12 *
13 * For more information, see tools/objtool/Documentation/stack-validation.txt.
14 */
15
16#include <stdio.h>
17#include <stdbool.h>
18#include <string.h>
19#include <stdlib.h>
20#include <subcmd/exec-cmd.h>
21#include <subcmd/pager.h>
22#include <linux/kernel.h>
23
24#include "builtin.h"
25#include "objtool.h"
26#include "warn.h"
27
28struct cmd_struct {
29	const char *name;
30	int (*fn)(int, const char **);
31	const char *help;
32};
33
34static const char objtool_usage_string[] =
35	"objtool COMMAND [ARGS]";
36
37static struct cmd_struct objtool_cmds[] = {
38	{"check",	cmd_check,	"Perform stack metadata validation on an object file" },
39	{"orc",		cmd_orc,	"Generate in-place ORC unwind tables for an object file" },
40};
41
42bool help;
43
44const char *objname;
45static struct objtool_file file;
46
47struct objtool_file *objtool_open_read(const char *_objname)
48{
49	if (objname) {
50		if (strcmp(objname, _objname)) {
51			WARN("won't handle more than one file at a time");
52			return NULL;
53		}
54		return &file;
55	}
56	objname = _objname;
57
58	file.elf = elf_open_read(objname, O_RDWR);
59	if (!file.elf)
60		return NULL;
61
62	INIT_LIST_HEAD(&file.insn_list);
63	hash_init(file.insn_hash);
64	INIT_LIST_HEAD(&file.retpoline_call_list);
65	INIT_LIST_HEAD(&file.return_thunk_list);
66	INIT_LIST_HEAD(&file.static_call_list);
67	file.c_file = !vmlinux && find_section_by_name(file.elf, ".comment");
68	file.ignore_unreachables = no_unreachable;
69	file.hints = false;
70
71	return &file;
72}
73
74static void cmd_usage(void)
75{
76	unsigned int i, longest = 0;
77
78	printf("\n usage: %s\n\n", objtool_usage_string);
79
80	for (i = 0; i < ARRAY_SIZE(objtool_cmds); i++) {
81		if (longest < strlen(objtool_cmds[i].name))
82			longest = strlen(objtool_cmds[i].name);
83	}
84
85	puts(" Commands:");
86	for (i = 0; i < ARRAY_SIZE(objtool_cmds); i++) {
87		printf("   %-*s   ", longest, objtool_cmds[i].name);
88		puts(objtool_cmds[i].help);
89	}
90
91	printf("\n");
92
93	if (!help)
94		exit(129);
95	exit(0);
96}
97
98static void handle_options(int *argc, const char ***argv)
99{
100	while (*argc > 0) {
101		const char *cmd = (*argv)[0];
102
103		if (cmd[0] != '-')
104			break;
105
106		if (!strcmp(cmd, "--help") || !strcmp(cmd, "-h")) {
107			help = true;
108			break;
109		} else {
110			fprintf(stderr, "Unknown option: %s\n", cmd);
111			cmd_usage();
112		}
113
114		(*argv)++;
115		(*argc)--;
116	}
117}
118
119static void handle_internal_command(int argc, const char **argv)
120{
121	const char *cmd = argv[0];
122	unsigned int i, ret;
123
124	for (i = 0; i < ARRAY_SIZE(objtool_cmds); i++) {
125		struct cmd_struct *p = objtool_cmds+i;
126
127		if (strcmp(p->name, cmd))
128			continue;
129
130		ret = p->fn(argc, argv);
131
132		exit(ret);
133	}
134
135	cmd_usage();
136}
137
138int main(int argc, const char **argv)
139{
140	static const char *UNUSED = "OBJTOOL_NOT_IMPLEMENTED";
141
142	/* libsubcmd init */
143	exec_cmd_init("objtool", UNUSED, UNUSED, UNUSED);
144	pager_init(UNUSED);
145
146	argv++;
147	argc--;
148	handle_options(&argc, &argv);
149
150	if (!argc || help)
151		cmd_usage();
152
153	handle_internal_command(argc, argv);
154
155	return 0;
156}
157